197 research outputs found

    A Survey From Distributed Machine Learning to Distributed Deep Learning

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    Artificial intelligence has achieved significant success in handling complex tasks in recent years. This success is due to advances in machine learning algorithms and hardware acceleration. In order to obtain more accurate results and solve more complex problems, algorithms must be trained with more data. This huge amount of data could be time-consuming to process and require a great deal of computation. This solution could be achieved by distributing the data and algorithm across several machines, which is known as distributed machine learning. There has been considerable effort put into distributed machine learning algorithms, and different methods have been proposed so far. In this article, we present a comprehensive summary of the current state-of-the-art in the field through the review of these algorithms. We divide this algorithms in classification and clustering (traditional machine learning), deep learning and deep reinforcement learning groups. Distributed deep learning has gained more attention in recent years and most of studies worked on this algorithms. As a result, most of the articles we discussed here belong to this category. Based on our investigation of algorithms, we highlight limitations that should be addressed in future research

    Outline of changes in cortisol and melatonin circadian rhythms in the security guards of Shiraz University of Medical Sciences

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    Background: According to the literature, a large number of people working in industries and service providing personnel, such as firefighters, physicians, and nurses are shift workers. The spread of shift working in industrial societies and the incidence of the problems resulting from shift working have caused the researchers to conduct studies on this issue. The present study also aimed to investigate melatonin and cortisol circadian rhythms in the security guards of Shiraz University of Medical Sciences, Shiraz, Iran. Methods: The present study was conducted on 20 security guards of Shiraz University of Medical Sciences. In order to collect the study data, blood samples were taken from the study subjects in different times of the day (1, 4, 7, 10, 13, 16, 19, and 22) and cortisol and melatonin levels were determined using the radioimmunoassay and enzyme immunoassay techniques, respectively. Results: The results showed that as the intensity of light increased at night, the plasma cortisol level increased, as well. Besides, no statistically significant difference was found between the plasma cortisol levels in natural light and 4500-lux light. On the other hand, a significant difference was observed between the plasma cortisol levels in natural light and 9000-lux light as well as 4500- and 9000-lux lights. The study findings also showed that as the intensity of light increased at night, the plasma melatonin level decreased. In addition, a statistically significant difference was found between the plasma melatonin levels in natural light and 4500-lux light. Nevertheless, no significant difference was observed between the plasma melatonin levels in the natural light and 9000-lux light as well as 4500- and 9000-lux lights. Conclusions: The present study aimed to investigate the subsequences of shift working in the security guards of Shiraz University of Medical Sciences and showed that occupational exposure to bright light could affect some biological markers, such as melatonin and cortisol secretion

    Outline of changes in cortisol and melatonin circadian rhythms in the security guards of Shiraz University of Medical Sciences

    Get PDF
    Background: According to the literature, a large number of people working in industries and service providing personnel, such as firefighters, physicians, and nurses are shift workers. The spread of shift working in industrial societies and the incidence of the problems resulting from shift working have caused the researchers to conduct studies on this issue. The present study also aimed to investigate melatonin and cortisol circadian rhythms in the security guards of Shiraz University of Medical Sciences, Shiraz, Iran. Methods: The present study was conducted on 20 security guards of Shiraz University of Medical Sciences. In order to collect the study data, blood samples were taken from the study subjects in different times of the day (1, 4, 7, 10, 13, 16, 19, and 22) and cortisol and melatonin levels were determined using the radioimmunoassay and enzyme immunoassay techniques, respectively. Results: The results showed that as the intensity of light increased at night, the plasma cortisol level increased, as well. Besides, no statistically significant difference was found between the plasma cortisol levels in natural light and 4500-lux light. On the other hand, a significant difference was observed between the plasma cortisol levels in natural light and 9000-lux light as well as 4500- and 9000-lux lights. The study findings also showed that as the intensity of light increased at night, the plasma melatonin level decreased. In addition, a statistically significant difference was found between the plasma melatonin levels in natural light and 4500-lux light. Nevertheless, no significant difference was observed between the plasma melatonin levels in the natural light and 9000-lux light as well as 4500- and 9000-lux lights. Conclusions: The present study aimed to investigate the subsequences of shift working in the security guards of Shiraz University of Medical Sciences and showed that occupational exposure to bright light could affect some biological markers, such as melatonin and cortisol secretion

    Stabilization and dewatering of wastewater treatment plants sludge using the Fenton process

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    Wastewater sludge typically contains large amounts of water and organic materials; therefore, its stabilization and dewatering is of particular importance. In this study, Fenton oxidation process is used for stabilization and dewatering of sludge in the output of a wastewater treatment plant. To evaluate the sludge stabilization and dewatering, specific resistance to filtration (SRF), volatile organic compounds (VSS), total suspended solids (TSS), soluble chemical oxygen demand (SCOD) and heterotrophic bacteria were measured. During the experiment, the optimal values of various parameters such as pH (2-9), hydrogen peroxide (0.015- 0.18mol/L), Fe2+ (0.008- 0.1mol/L) and time (5 - 60 minutes) for optimum sludge dewatering and stabilization were investigated. The results showed that the highest percentages of SRF reduction and removal rates of SCOD, VSS and TSS were 99.48, 61, 42, and 41 percent respectively. These results were obtained in optimum pH 5, 0.05 mol/l Fe2+, 0.12 mol/l hydrogen peroxide, and the retention time of 15 minutes. The removal rate of heterotrophic bacteria increased with increasing dose of hydrogen peroxide, so that a removal rate of 84 percent was observed at a dose of 0.18 mol/l. In general, Fenton process can reduce volatile organic materials and chemical oxygen demand of the sludge resulting in its significant stabilization and dewatering. In general, Fenton process can reduce volatile organic materials and chemical oxygen demand of the sludge resulting in its significant stabilization and dewatering

    Discovering the Symptom Patterns of COVID-19 from Recovered and Deceased Patients Using Apriori Association Rule Mining

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    The COVID-19 pandemic has a devastating impact globally, claiming millions of lives and causing significant social and economic disruptions. In order to optimize decision-making and allocate limited resources, it is essential to identify COVID-19 symptoms and determine the severity of each case. Machine learning algorithms offer a potent tool in the medical field, particularly in mining clinical datasets for useful information and guiding scientific decisions. Association rule mining is a machine learning technique for extracting hidden patterns from data. This paper presents an application of association rule mining based Apriori algorithm to discover symptom patterns from COVID-19 patients. The study, using 2875 records of patient, identified the most common symptoms as apnea (72%), cough (64%), fever (59%), weakness (18%), myalgia (14.5%), and sore throat (12%). The proposed method provides clinicians with valuable insight into disease that can assist them in managing and treating it effectively

    Virtual machine placement in cloud using artificial bee colony and imperialist competitive algorithm

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    Increasing resource efficiency and reducing energy consumption are significant challenges in cloud environments. Placing virtual machines is essential in improving cloud systems’ performance. This paper presents a hybrid method using the artificial bee colony and imperialist competitive algorithm to reduce provider costs and decrease client expenditure. Implementation of the proposed plan in the CloudSim simulation environment indicates the proposed method performs better than the Monarch butterfly optimization and salp swarm algorithms regarding energy consumption and resource usage. Moreover, average central processing unit (CPU) and random-access memory (RAM) usage and the number of host shutdowns show better results for the proposed model

    Multiple Arrhythmogenic Substrate for Tachycardia in a Patient with Frequent Palpitations

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    We report a 26-year-old woman with frequent episodes of palpitation and dizziness. Resting electrocardiography showed no evidence of ventricular preexcitation. During electrophysiologic study, a concealed right posteroseptal accessory pathway was detected and orthodromic atrioventricular reentrant tachycardia incorporating this pathway as a retrograde limb was reproducibly induced. After successful ablation of right posteroseptal accessory pathway, another tachycardia was induced using a concealed right posterolateral accessory pathway in tachycardia circuit. After loss of retrograde conduction of second accessory pathway with radiofrequency ablation, dual atrioventricular nodal physiology was detected and typical atrioventricular nodal reentrant tachycardia was repeatedly induced. Slow pathway ablation was done successfully. Finally sustained self-terminating atrial tachycardia was induced under isoproterenol infusion but no attempt was made for ablation. During 8-month follow-up, no recurrence of symptoms attributable to tachycardia was observed

    The Effectiveness of Cognitive-Behavioral Education on Students' Communication Problems and Perfectionism

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    In the present study, the effectiveness of cognitive-behavioral education on the communication difficulties and perfectionism of students was studied. The research design was pre-test and post-test method with control group. The statistical population of this study included all students in district 2 of Tehran in the academic year of 2017-2018. The sample size consisted of 30 members of this community, which was first selected by simple random sampling method. And divided into two groups of 15 patients. The questionnaire of perfectionism and multidimensional perfectionism were used to measure the communication difficulties of the questionnaire and perfectionism. After selecting the test group and the test, experimental intervention (cognitive-behavioral training) was performed on the experimental group for 8 sessions of 90 minutes and one session per week, and after completing the training program from each of the two post-test groups action, it came  to analyze the collected data, in addition to descriptive statistics, one-way covariance analysis was used. Results showed that cognitive-behavioral education improves the subscales of communication difficulties, explicitly and publicly, In terms of others, aggression, support and participation, and perfectionism, and under the subcategory of democratship (concern about mistakes-individual measures-parents expectations-doubts about things), the test group has been compared with the group. But under the scales (openness-dependence) and (parental critique-the tendency to order and organization) was not affected. The conclusion is that cognitive-behavioral learning can improve the interpersonal difficulties and perfectionism of students. Keyword: Cognitive-Behavioral Education, Communication Problems-Perfectionism. DOI: 10.7176/RHSS/9-3-1

    Coexistence of Atrioventricular Nodal Reentrant Tachycardia and Idiopathic Left Ventricular Outflow-Tract Tachycardia

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    Double tachycardia is a relatively rare condition. We describe a 21 year old woman with history of frequent palpitations. In one of these episodes, she had wide complex tachycardia with right bundle branch and inferior axis morphology. A typical atrioventricular nodal tachycardia was induced during electrophysiologic study, aimed at induction of clinically documented tachycardia. Initially no ventricular tachycardia was inducible. After successful ablation of slow pathway, a wide complex tachycardia was induced by programmed stimulation from right ventricular outflow tract. Mapping localized the focus of tachycardia in left ventricular outflow tract and successfully ablated via retrograde aortic approach. During 7 month's follow-up, she has been symptom free with no recurrence. This work describes successful ablation of rare combination of typical atrioventricular nodal tachycardia and left ventricular outflow tract tachycardia in the same patient during one session

    Prevalence of Self-medication with Antibiotics amongst Clients Referred to Outpatient University Dental Clinics in Iranian Population: A Questionnaire-based Study

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    Introduction: Self-medication with antibiotics may increase the risk of inappropriate use and development of antibiotic-resistant bacteria. The aim of this study was to determine the prevalence of self-medication with antibiotics amongst dental outpatients in Iranian population.  Methods and Materials: One thousand and two hundred of dentistry patients, who were referred to dental school clinics in ten major provinces of Iran, participated in this study. A valid self-administered questionnaire regarding self-medication with antibiotics in case of dental pain was used to collect data. Data were analysed using descriptive statistics and Logistic regression analysis. Results: In our study population, the prevalence of self-medication was 42.6%. Amongst the Iranian cities, the highest prevalence of self-medication with antibiotics belonged to the city of Bandar Abbas (64%) and the lowest was seen in the city of Kerman (27.3%). Men were more likely to take antibiotics. Amoxicillin was the mostly used antibiotic. Severe pain, previous self-medications and high costs of dental visits were the most common reasons for self-medication with antibiotics in the investigated population. In addition, the present study showed that marriage, acceptable financial status and high level of education could decrease self-medication with antibiotics. Conclusions: In the current investigation, an alarming fact was that self-medication for dental problems seemed very common amongst the studied population. One of its most important consequences was bacterial resistance. Therefore, there should be plans to promote and prioritize public health awareness and encourage general public’s motivation to reduce the practice of self-medication.Keywords: Antibiotics; Dental Clinics; Prevalence; Self-medicatio
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